Hardware interview practice
Choose a localized IR-drop repair
Sign-off shows a small cluster with dynamic IR drop beyond the limit. Timing slack is +180 ps, routing congestion is low, and the global power grid meets limits elsewhere. Which first change most directly targets the problem with the least unrelated disruption?
Choose one
Answer choices
- A. Insert data-path delay cells on every short timing path in the block, regardless of location.
- B. Declare the affected paths false so timing analysis no longer reports voltage-sensitive delay.
- C. Strengthen local power delivery near the cluster, such as adding local straps or vias, then recheck placement current density.
- D. Lower the clock period globally, because faster switching gives the local cells more voltage recovery time.